A dc, separately excited motor drives a constant-torque load.
a. If a resistance is added in series with the armature circuit, does the armature
current change? Explain why?
b. How does the speed changes in case (a)?
a. Separately excited motor means that flux ( k? ) remains constant. Now, since
the load is constant-torque, the armature current remains constant.
b. From the equation below, adding an Ra will reduce the speed.
You might also like to view...
What type notification relates to repairs that are always covered by the manufacturer to correct a safety or emission related concern?
A) Recall B) Technical Service Bulletin C) Both A and B D) Neither A nor B
What should be done when checking the refrigerant charge of an operating packaged unit?
a. Allow time for the operation of the unit to stabilize. b. Put the unit in economizer mode. c. Open all outdoor air dampers and close the return air dampers. d. Remove the supply air fan access panel.
A 1Ø compressor (CSIR) has proper voltage, starts and runs for about 5 seconds, then goes out on overload. Which of the following is most likely the problem?
a. The start relay contacts are welded closed. b. The start relay contacts are stuck open. c. The start capacitor is bad. d. The compressor is locked up.
In a reverse acting closed loop control system, the process variable and the controller output move in the same direction
Indicate whether the statement is true or false